At risk, prior to a breakthrough?

• Nicotine misused outside hospital in a risky location
• Once hit in crash, vulnerable
• About to take the plunge perhaps, mixing nicotine with heroin
• Destroyed nicotine, protecting hearts at risk

Wikipedia Word definitions in Wikipedia
On Thin Ice may refer to: On Thin Ice , an improvisational comedy group from Harvard On Thin Ice (TV series) , a documentary covering a race across Antarctica to reach the South Pole "On Thin Ice", the final episode of the BBC nature documentary Frozen ...

Wiktionary Word definitions in Wiktionary
a. (context idiomatic English) In a dangerous, hazardous, or delicate situation; at risk.