He was a lithe man named Shane Newman, with a long neck, reptilian nose and distinctive tattoos.

At the time, he was also an ice addict.

He walked up two flights of stairs, then took a lift to the sixth floor. He walked up more stairs, and tried the doors to the rooftop. They wouldn't budge.

Newman walked back down to the sixth level, and found a key in the lock of a communications room. He removed the key and hid inside.

A short time later he left the room, walked back upstairs, and forced the doors to the roof open.

Newman took his bag from his back, unzipped it, and removed a can of spray paint.

On a wall, visible from the honking and pinging and smoky streets below, he wrote four letters: N-O-S-T.

It is impossible to know how many times those four letters, the tag of Melbourne's most prolific graffiti artist, have been painted.

Many of them are in places where thousands of people can see them. Others, like those done on trains which are often scrubbed clean again within minutes, no longer exist.

But now, perhaps, Nost is no more. Newman, 35, was jailed on Tuesday for theft, criminal damage and robbery-related offences.

Magistrate Johanna Metcalf said it was a chance to break his habit, and leave the pipe and the spray can behind. Newman remained silent, a wooden crucifix hanging from his neck, as he was sentenced.

He was sentenced to seven months' jail, but will be free in a month because of the time he has already served in custody. Remand has not been easy; Newman was subject to a vicious bashing, and has been withdrawing from ice, Ms Metcalf heard.

Newman's barrister, Peter Matthews, told the court his client's life had been transformed after suffering a heart attack, which was linked to a congenital condition, but may have been exacerbated by his drug use.

As he was no longer able to perform physical labour, Mr Matthews said, Newman went from being a talented and hardworking bricklayer with a long-term partner to an ice addict.

While Newman's heart attack precipitated the end of his work as a bricklayer, it did not halt his tagging. In fact, according to another tagger, it probably helped it; Nost appeared far more frequently after the heart attack, as Newman fell further into the grips of ice.

"The whole thing is to do with drugs," the fellow tagger said. "He could just keep going and take risks. If he was straight, he wouldn't be doing it."

Newman was arrested last year, and again this year after being released on bail.

Mr Matthews said Newman had been raised by supportive parents in the outer south-east, and had a strong relationship with his sister's young son, who also suffered heart problems.

His partner and sister were in the Melbourne Magistrates Court for the sentencing.

Police alleged he had stolen property including keys which allowed access to V/Line trains, bikes, and a camera, and that he broke into buildings including a spray paint store.

In several cases, Nost was identified by his tattoos, including a wishbone and "cut-throat razor blade" on his hands.

On April 10 last year, Newman and a regular accomplice, who uses the tag Lamb, painted their monikers in green and black paint on a retaining wall near the St Kilda Road tram junction.

When Newman was asked about the vandalism, according to court documents, he demurred.

"Do you know what Nost means?" a police officer asked him. "No," he replied.

The officer then asked if he had ever used it as a spray paint tag, which he denied, before offering a line which could have been cheek, a nod at his notoriety or neither: "I've seen it," he said.