Have a drink with The Big Man? Yup, it's another Yujiro Ishihara（石原裕次郎）ballad of life and love. Titled "Yuusha tachi" (The Heroes), it's got all the tropes of an Ishihara song from the 70s and 80s: the melancholy strings, the mournful female chorus and of course, the languid Old Parr vocals of the man himself.
Created in 1982 by songwriters Keisuke Hama and Rei Nakanishi（浜圭介・なかにし礼）, just reading the title, looking at the video and noticing the similarity of this song with another one of Ishihara's old chestnuts, "Yoake no Machi"（夜明けの街）, I figured that this had to be another theme song for the long-running detective series "Seibu Keisatsu"（西部警察...Police: Western Division）. And looking things up on J-Wiki, yep, that guess turned out to be correct. To be specific, "Yuusha tachi" was the ending theme for the 2nd series of "Seibu Keisatsu" that lasted from 1982 to 1983.
It's interesting listening to these ballads in Ishihara's later years when I remember his earlier songs when he was that young lanky hellraiser. There is very much of the seen-it-all/heard-it-all/did-it-all atmosphere in songs like "Yuusha tachi", although Nakanishi's lyrics still have The Big Man quietly encouraging the listener to hang in there and not give up the fight. He could have been easily advising his officers over a stiff drink.